Britain is poised to become the main European refuelling hub for secret CIA flights carrying terrorist suspects for interrogation in North Africa and the Middle East.

Despite protests by MPs and MSPs, the UK government has taken no action either to halt the clandestine flights or demand to know whether prisoners were on board the 390 known to have landed at Scottish and English airfields since 2001.

They are called “rendition” missions. This is the White House-sanctioned process of moving al Qaeda and other Islamic terrorist prisoners to third countries where they can be interrogated beyond the reach of US and European human rights’ legislation. The countries to which captives have been taken for questioning by local security forces have been accused by the UN of employing torture to obtain information.

Officials in Germany, Spain, Sweden and Norway have opened criminal investigations into possible violations of national and international law on the issue. Italy has filed a formal extradition request naming 22 CIA agents allegedly involved in the kidnap of a radical Muslim cleric in 2003.

Ireland and Denmark have lodged protests over the pit-stop presence of CIA-operated aircraft on their territory en route for Guantanamo Bay in Cuba or “ghost” prisons elsewhere in the world. Denmark has even asked the CIA to avoid using its airspace when transporting prisoners.

A German intelligence source said: “Britain may soon be one of the few countries, if not the only one, still willing to accept rendition missions via its sovereign territory.”

The Herald has revealed Scottish RAF bases and civilian airports had played host to the 170 “rendition” missions en route to or returning from Egypt, Morocco, Uzbekistan, Afghanistan, Syria and Jordan.

Glasgow and Prestwick airports handled 149 of the refuelling stops, including a number of overnight stays. RAF Leuchars, Edinburgh, Inverness and Wick were the other locations.

Professor Martin Scheinin, of the UN’s human rights commission, said: “When several states, by co-operating with each other, breach their obligations under international law simultaneously where torture might be involved, then all bear individual responsibility. I have submitted a list of detailed questions to the government of the UK over rendition flights.”

A source from Germany’s spy service said: “While most European governments initially turned a blind eye to rendition flights in the immediate aftermath of September 11, the embarrassment factor involved once the media realised that suspects were being abducted for torture at the hands of third parties means that these missions can no longer be carried out with impunity.

“Austria scrambled fighters to intercept an unauthorised CIA flight two years ago and our own government is increasingly hostile to US arrogance in assuming that Ramstein air base is US territory.”

Spain this week opened a judicial inquiry into claims that CIA flights used Majorca and the Canary Islands.

A CIA spokesman said the agency carried out rendition flights only via “countries which are political allies and whose intelligence services grant permission”.